The proposed study is an effectiveness trial of a quality improvement intervention for the treatment of adolescent and young adult depression within managed primary care settings under usual care conditions. Depression in youth interferes with functioning during a critical developmental period and is associated with adverse outcomes, such as suicide, risk for drug and alcohol problems, and adult depression. Does improving rates of use of efficacious treatment improve outcomes, and at what costs? To address this question, we propose a randomized trial at the clinic level to evaluate an intervention featuring patient and primary care-provider education about treatment for depression, coupled with clinic resources that facilitate initiation and provision of appropriate care, whether medication management or full-course Cognitive Behavioral Therapy. We assess intervention effects, compared to care as usual, on quality of care, satisfaction with care, clinical symptoms and daily functioning, service use and costs, and indirect costs and parental psychological distress. This proposal is a unique opportunity to extend Partners in Care (PIC), an AHCPR PORT-II on the cost-effectiveness of quality improvement interventions for adult depressed patients in primary care. This proposal uses PIC intervention materials and study measures. Patients identified as depressed in intervention and control clinics will be evaluated at baseline, 6-months, 12 months, and 18 months. We hypothesize that the intervention will improve quality of care, and through quality of care, improve clinical and functioning outcomes for depressed youths and reduce family burden. The study has an interdisciplinary team including psychiatrists, psychologists, nurses, primary care clinicians, statisticians, sociologists, and economists.